His comments are:
This patch fixes the problem of modern Kerberos using "derived keys"
to encrypt the authenticator by disabling the authenticator check
for all derived keys enctypes.
I think I've got all the bugfixes that Jeffrey and I discussed rolled
into this. There were some problems with Jeffrey's code to convert
the authenticator's Kerberos timestring into struct tm (e.g. Z, -1900;
it helps to have an actual decryptable authenticator to play with).
So I've shamelessly pushed in my code, while stealing some bits from
Jeffrey.
Note that since some private kssl functions were exported, the
simplest way to rebuild the number table was to toss everything that
was new since OpenSSL 0.9.6b. This is safe, since those functions
have not yet been exported in an OpenSSL release. Beware, people who
trust intermediary snapshots!
His comments are:
. adds use of replay cache to protect against replay attacks
. adds functions kssl_tgt_is_available() and
kssl_keytab_is_available() which are used within s3_lib.c
and ssl_lib.c to determine at runtime whether or not
KRB5 ciphers can be supported during the current session.
Jeffrey Altman <jaltman@columbia.edu>
(Really, the time that's being parsed is a GeneralizedTime, so if
ASN1_GENERALIZEDTIME_get() ever gets implemented, it should be used
instead)
His comments are:
. Fixed all of the Windows dynamic loading functions, prototypes, etc.
. Corrected all of the unsigned/signed comparison warnings
. Replaced the references to krb5_cksumarray[] for two reasons.
First, it was an internal variable that should not have been
referenced outside the library; nor could it have been with
a shared library with restricted exports. Second, the
variable is no longer used in current Kerberos implementations.
I replaced the code with equivalent functionality using functions
that are exported from the library.
SSL according to RFC 2712. His comment is:
This is a patch to openssl-SNAP-20010702 to support Kerberized SSL
authentication. I'm expecting to have the full kssl-0.5 kit up on
sourceforge by the end of the week. The full kit includes patches
for mod-ssl, apache, and a few text clients. The sourceforge URL
is http://sourceforge.net/projects/kssl/ .
Thanks to a note from Simon Wilkinson I've replaced my KRB5 AP_REQ
message with a real KerberosWrapper struct. I think this is fully
RFC 2712 compliant now, including support for the optional
authenticator field. I also added openssl-style ASN.1 macros for
a few Kerberos structs; see crypto/krb5/ if you're interested.
applications to use EVP. Add missing calls to HMAC_cleanup() and
don't assume HMAC_CTX can be copied using memcpy().
Note: this is almost identical to the patch submitted to openssl-dev
by Verdon Walker <VWalker@novell.com> except some redundant
EVP_add_digest_()/EVP_cleanup() calls were removed and some changes
made to avoid compiler warnings.
compiler bug reported in <01032110293775.22278@weba3.iname.net>
(the '++seq[i]' condition is evaluated as 256 rather than 0
when the previous value is 255).
an SSL_CTX's session cache, it is necessary to compare the ssl_version at
the same time (a conflict is defined, courtesy of SSL_SESSION_cmp(), as a
matching id/id_length pair and a matching ssl_version). However, the
SSL_SESSION that will result from the current negotiation does not
necessarily have the same ssl version as the "SSL_METHOD" in use by the
SSL_CTX - part of the work in a handshake is to agree on an ssl version!
This is fixed by having the check function accept an SSL pointer rather
than the SSL_CTX it belongs to.
[Thanks to Lutz for illuminating the full extent of my stupidity]
and make all files the depend on it include it without prefixing it
with openssl/.
This means that all Makefiles will have $(TOP) as one of the include
directories.
the ID will be padded out to 16 bytes if the callback attempted to generate
a shorter one. The problem is that the uniqueness checking function used in
callbacks may mistakenly think a 9-byte ID is unique when in fact its
padded 16-byte version is not. This makes the checking function detect
SSLv2 cases, and ensures the padded form is checked rather than the shorter
one passed by the callback.
SSL/TLS session IDs in a server. According to RFC2246, the session ID is an
arbitrary value chosen by the server. It can be useful to have some control
over this "arbitrary value" so as to choose it in ways that can aid in
things like external session caching and balancing (eg. clustering). The
default session ID generation is to fill the ID with random data.
The callback used by default is built in to ssl_sess.c, but registering a
callback in an SSL_CTX or in a particular SSL overrides this. BTW: SSL
callbacks will override SSL_CTX callbacks, and a new SSL structure inherits
any callback set in its 'parent' SSL_CTX. The header comments describe how
this mechanism ticks, and source code comments describe (hopefully) why it
ticks the way it does.
Man pages are on the way ...
[NB: Lutz was also hacking away and helping me to figure out how best to do
this.]
sure they are available in opensslconf.h, by giving them names starting
with "OPENSSL_" to avoid conflicts with other packages and by making
sure e_os2.h will cover all platform-specific cases together with
opensslconf.h.
I've checked fairly well that nothing breaks with this (apart from
external software that will adapt if they have used something like
NO_KRB5), but I can't guarantee it completely, so a review of this
change would be a good thing.
